Comparing SF-6D and EQ-5D utilities across groups differing in health status

Area of Science:

• Health Economics
• Patient-Reported Outcomes
• Psychometrics

Background:

• Health utility measures are crucial for economic evaluations in healthcare.
• The EQ-5D (EuroQol 5 Dimensions) and SF-6D (Short Form 6 Dimensions) are widely used instruments.
• Understanding their comparative performance across diverse populations is essential.

Purpose of the Study:

• To compare the EQ-5D and SF-6D in a representative Greek general population sample.
• To examine mean utility score differences between the two instruments across various socio-demographic and clinical groups.
• To validate findings in a sample of individuals with diabetes.

Main Methods:

• Utilized Pearson's r and Intraclass Correlation Coefficient (ICC) to assess association and agreement.
• Employed paired-samples t-tests to identify significant score differences, defining minimally important differences (MIDs) at >0.03.
• Classified participants into health status groups using the EQ-Visual Analogue Scale (EQ-VAS).

Main Results:

• Strong overall agreement and correlation between EQ-5D and SF-6D (ICC=0.536, r=0.662).
• EQ-5D scores were significantly higher in healthier individuals, with differences meeting MIDs.
• SF-6D scores were predominantly higher in individuals with clinical conditions, a pattern consistent in the diabetes sample.

Conclusions:

• Confirmed hypotheses that EQ-5D yields higher scores in healthier populations and SF-6D in less healthy groups.
• Demonstrated that EQ-5D and SF-6D measure discrepancies create utility differences across health status groups.
• Highlighted the need for further within-sample investigation of these measurement discrepancies.